This collects the info needed to show and launch live wallpaper
configuration activities. Also filters out wallpapers that don't
contain the wallpaper meta-data.
Change-Id: I8b3fb17cc436396bd714e43131997c135b5e1b7c
This change requires changing the signature and shared user id of Launcher2, we
will have to revert this once we move the wallpapers picker back to Settings.